The present invention generally relates to apparatus for cleaning floor surfaces, particularly to floor surface cleaning apparatus which applies cleaning solution to the floor surface and then vacuums the soiled cleaning solution from the floor surface, more particularly to carpet extractors, and specifically to carpet extractors having the ability to do both restorative cleaning and maintenance cleaning of carpeted surfaces.
The most common method of cleaning carpeted surfaces is with a carpet extractor. These machines consist of a clean solution tank with some means to apply solution to the floor surface, an agitation means for cleaning the floor surface, a dirty solution tank, and a vacuum means to pick the dirty solution off the floor surface after it is agitated. The tanks and systems performing these operations are usually attached to and carried by some type of chassis, which also may have provisions for a power source, wheels, and a means to transport the machine.
There are two types of carpet extraction, restorative and maintenance. Restorative cleaning is a deep cleaning process that is performed to remove soil and stains that normal dry vacuuming can not. Restorative cleaning requires a relatively high volume of solution to wash and flush soil and stains from deep within the carpeted surface. One of the negatives of restorative cleaning is the amount of cleaning solution that is retained within the carpet fibers and backing when the process is completed. Until the retained solution evaporates from the surface, the carpeted surface typically is not used, as soil that comes in contact with the carpeted surface while it is damp tends to stick to the surface.
Maintenance cleaning involves a cleaning of the upper exterior of the carpeted surface only. Maintenance cleaning requires a relatively low volume of solution resulting in less residual solution left in the carpeted surface and a shorter dry time.
Prior to the present invention, carpet extractors have been set up to do either maintenance cleaning or restorative cleaning. Since the solution typically is dispensed at a fixed rate, the only way to vary the amount of solution applied to a given area of carpeted surface was by varying the speed of the machine.
Thus, a need exists for floor surface cleaning apparatus which is selectively operative in one of two cleaning modes, and in the preferred form, restorative and maintenance carpet extraction.